K240049 · Metric Medical Devices, Inc. · KTT · May 29, 2024 · Orthopedic
Device Facts
Record ID
K240049
Device Name
LINK(TM) External Fixator
Applicant
Metric Medical Devices, Inc.
Product Code
KTT · Orthopedic
Decision Date
May 29, 2024
Decision
SESE
Submission Type
Traditional
Regulation
21 CFR 888.3030
Device Class
Class 2
Attributes
Therapeutic
Indications for Use
The LINK™ External Fixator is indicated for 1) hand and foot bone fragment and joint arthrodesis, 2) fixation of proximal tibial metaphysis osteotomy and 3) adjunctive fixation of small bone fragments (i.e. small fragments of bone which are not comminuted to the extent to preclude LINK™ Bone Pin placement). These fragments may be located in long bones such as the femur, fibula and tibia in the lower extremities; the humerus, ulna or radius in the upper extremities; the clavicle and ribs; and in flat bones such as the pelvis, scapula and sternum.
Device Story
Single-use external fixator; stainless steel flat spring formed into box shape; applies forces/moments to bone pins/K-wires/Steinmann pins embedded in bone; actively pulls together/compresses or distracts bone. Used in clinical setting; operated by physician. Procedure: fixator held with surgical needle drivers; pins advanced through fixator, skin, and into bone; needle drivers released; fixator bridge shortens; side elements swing outward to create moments on pins. Includes removable silicon elastomer cover to protect patient from pin ends. Benefits: dynamic compression/distraction of bone fragments to facilitate healing.
Clinical Evidence
Bench testing only. Testing included construct pull-out, 4-point bending for bone pins, 4-point bending for fixator construct in bone analog, static ultimate strength in tension bending, fatigue in tension bending, and measurement of force applied to bone.
Indicated for hand/foot bone fragment fixation, joint arthrodesis, proximal tibial metaphysis osteotomy fixation, and adjunctive fixation of small bone fragments in long bones (femur, fibula, tibia, humerus, ulna, radius, clavicle, ribs) and flat bones (pelvis, scapula, sternum).
Regulatory Classification
Identification
Single/multiple component metallic bone fixation appliances and accessories are devices intended to be implanted consisting of one or more metallic components and their metallic fasteners. The devices contain a plate, a nail/plate combination, or a blade/plate combination that are made of alloys, such as cobalt-chromium-molybdenum, stainless steel, and titanium, that are intended to be held in position with fasteners, such as screws and nails, or bolts, nuts, and washers. These devices are used for fixation of fractures of the proximal or distal end of long bones, such as intracapsular, intertrochanteric, intercervical, supracondylar, or condylar fractures of the femur; for fusion of a joint; or for surgical procedures that involve cutting a bone. The devices may be implanted or attached through the skin so that a pulling force (traction) may be applied to the skeletal system.
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Image /page/0/Picture/0 description: The image contains the logo of the U.S. Food and Drug Administration (FDA). On the left is the Department of Health & Human Services logo. To the right of that is the FDA logo, which is a blue square with the letters "FDA" in white. To the right of the FDA logo is the text "U.S. FOOD & DRUG ADMINISTRATION" in blue.
May 29, 2024
Metric Medical Devices, Inc. William Casey Fox President 846 Silver Springs Helotes. Texas 78023
Re: K240049
Trade/Device Name: LINK™ External Fixator Regulation Number: 21 CFR 888.3030 Regulation Name: Single/multiple component metallic bone fixation appliances and accessories Regulatory Class: Class II Product Code: KTT Dated: January 5, 2024 Received: January 8, 2024
Dear William Casey Fox:
We have reviewed your section 510(k) premarket notification of intent to market the device referenced above and have determined the device is substantially equivalent (for the indications for use stated in the enclosure) to legally marketed predicate devices marketed in interstate commerce prior to May 28, 1976, the enactment date of the Medical Device Amendments, or to devices that have been reclassified in accordance with the provisions of the Federal Food, Drug, and Cosmetic Act (the Act) that do not require approval of a premarket approval application (PMA). You may, therefore, market the device, subject to the general controls provisions of the Act. Although this letter refers to your product as a device, please be aware that some cleared products may instead be combination products. The 510(k) Premarket Notification Database available at https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfpmn/pmn.cfm identifies combination product submissions. The general controls provisions of the Act include requirements for annual registration, listing of devices, good manufacturing practice, labeling, and prohibitions against misbranding and adulteration. Please note: CDRH does not evaluate information related to contract liability warranties. We remind you, however, that device labeling must be truthful and not misleading.
If your device is classified (see above) into either class II (Special Controls) or class III (PMA), it may be subject to additional controls. Existing major regulations affecting your device can be found in the Code of Federal Regulations, Title 21, Parts 800 to 898. In addition, FDA may publish further announcements concerning your device in the Federal Register.
Additional information about changes that may require a new premarket notification are provided in the FDA guidance documents entitled "Deciding When to Submit a 510(k) for a Change to an Existing Device"
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(https://www.fda.gov/media/99812/download) and "Deciding When to Submit a 510(k) for a Software Change to an Existing Device" (https://www.fda.gov/media/99785/download).
Your device is also subject to, among other requirements, the Quality System (QS) regulation (21 CFR Part 820), which includes, but is not limited to, 21 CFR 820.30. Design controls; 21 CFR 820.90. Nonconforming product; and 21 CFR 820.100, Corrective and preventive action. Please note that regardless of whether a change requires premarket review. the OS regulation requires device manufacturers to review and approve changes to device design and production (21 CFR 820.30 and 21 CFR 820.70) and document changes and approvals in the device master record (21 CFR 820.181).
Please be advised that FDA's issuance of a substantial equivalence determination does not mean that FDA has made a determination that your device complies with other requirements of the Act or any Federal statutes and regulations administered by other Federal agencies. You must comply with all the Act's requirements, including, but not limited to: registration and listing (21 CFR Part 807); labeling (21 CFR Part 801); medical device reporting of medical device-related adverse events) (21 CFR Part 803) for devices or postmarketing safety reporting (21 CFR Part 4, Subpart B) for combination products (see https://www.fda.gov/combination-products/guidance-regulatory-information/postmarketing-safety-reportingcombination-products); good manufacturing practice requirements as set forth in the quality systems (QS) regulation (21 CFR Part 820) for devices or current good manufacturing practices (21 CFR Part 4, Subpart A) for combination products; and, if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR Parts 1000-1050.
Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21 CFR 807.97). For questions regarding the reporting of adverse events under the MDR regulation (21 CFR Part 803), please go to https://www.fda.gov/medical-device-safety/medical-device-reportingmdr-how-report-medical-device-problems.
For comprehensive regulatory information about mediation-emitting products, including information about labeling regulations, please see Device Advice (https://www.fda.gov/medicaldevices/device-advice-comprehensive-regulatory-assistance) and CDRH Learn (https://www.fda.gov/training-and-continuing-education/cdrh-learn). Additionally, you may contact the Division of Industry and Consumer Education (DICE) to ask a question about a specific regulatory topic. See the DICE website (https://www.fda.gov/medical-device-advice-comprehensive-regulatoryassistance/contact-us-division-industry-and-consumer-education-dice) for more information or contact DICE by email (DICE@fda.hhs.gov) or phone (1-800-638-2041 or 301-796-7100).
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Sincerely,
# Lixin Liu -S
Lixin Liu, PhD Assistant Director DHT6A: Division of Joint Arthroplasty Devices OHT6: Office of Orthopedic Devices Office of Product Evaluation and Quality Center for Devices and Radiological Health
Enclosure
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#### DEPARTMENT OF HEALTH AND HUMAN SERVICES Food and Drug Administration
## Indications for Use
Form Approved: OMB No. 0910-0120 Expiration Date: 07/31/2026 See PRA Statement below.
### Submission Number (if known)
K240049
#### Device Name
LINK™ External Fixator
### Indications for Use (Describe)
The LINK™ External Fixator is indicated for 1) hand and foot bone fragment and joint arthrodesis, 2) fixation of proximal tibial metaphysis osteotomy and 3) adjunctive fixation of small bone fragments (i.e. small fragments of bone which are not comminuted to the extent to preclude LINK™ Bone Pin placement). These fragments may be located in long bones such as the femur, fibula and tibia in the lower extremities; the humerus, ulna or radius in the upper extremities; the clavicle and ribs; and in flat bones such as the pelvis, scapula and sternum.
Type of Use (Select one or both, as applicable)
図Prescription Use (Part 21 CFR 801 Subpart D)
□Over-The-Counter Use (21 CFR 801 Subpart C)
## CONTINUE ON A SEPARATE PAGE IF NEEDED.
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## *DO NOT SEND YOUR COMPLETED FORM TO THE PRA STAFF EMAIL ADDRESS BELOW.*
The burden time for this collection of information is estimated to average 79 hours per response, including the time to review instructions, search existing data sources, gather and maintain the data needed and complete and review the collection of information. Send comments regarding this burden estimate or any other aspect of this information collection, including suggestions for reducing this burden, to:
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# 510(k) Summary of Safety and Effectiveness
510(k) Summary As required by 21 CFR 807.92:
Name of Sponsor: Metric Medical Devices, Inc., 846 Silver Springs, Helotes, TX, 78023
Contact: William Casey Fox, Ph.D., P.E., President Phone: 210-535-6300 e-mail: fox@metricmd.com
Date Prepared: 3/5/2024
Device Trade Name: LINK™ External Fixator
Classification Name: Single/multiple component metallic bone fixation appliances and accessories
Common Name: Appliance, Fixation, Nail/Blade/Plate Combination, Multiple Component
Device classification: Class II per 21 CFR 888.3030
Product Code: KTT
Predicate Device: Gexfix External Fixation (K160972, product code KTT)
Reference Devices: ORTHOFIX MODULSYSTEM (K955848, product code JDW) and Super Staple™ Classic (K123363, product code JDR)
Indications for use: 1) hand and foot bone fragment and osteotomy fixation and joint arthrodesis, 2) fixation of proximal tibial metaphysis osteotomy and 3) adjunctive fixation of small bone fragments (i.e. small fragments of bone which are not comminuted to the extent to preclude LINK™ bone pin placement). These fragments may be located in long bones such as the femur, fibula and tibia in the lower extremities; the humerus, ulna or radius in the upper extremities; the clavicle and ribs; and in flat bones such as the pelvis, scapula and sternum.
Device Description: The LINK™ External Fixator is a single use External Fixator consisting of a stainless steel flat spring formed into a box shape so that when released it applies forces and moments to Bone Pins, K-wires or Steinmann pins embedded in bone to actively pull together and compress or distract bone.
In clinical use the LINK™ External Fixator is held with its holes aligned using surqical needle drivers while wires or pins are advanced through the LINK™ External Fixator, skin and into bone. Once pins are placed the needle drivers are released, the LINK™ External Fixator
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bridge shortens to apply forces and the LINK™'s side elements swing outward to create moments on the wires or pins.
The LINK™ External Fixator uses spring heat treated 17-7 stainless steel which is uniquely formed from a flat plate to create a shape changing spring. The Bone Pins in this kit are formed with 316 Stainless Steel. The LINK™ External Fixator has a separate removable silicon elastomer cover to protect the LINK™ External Fixator and the patient from the pin ends. Only the Bone Pins are in contact with the patient while the LINK™ External Fixator and its cover are external to the body and not intended for patient contact.
## Comparison of Technical Characteristics with the Predicate Device:
The LINK™ External Fixator is substantially equivalent to legally marketed Gexfix External Fixation (K160972, product code KTT) in indications for use, material, design and function. Any minor differences between these devices or their performance do not raise any different questions of safety and effectiveness.
| Parameter | LINK™ External Fixator | Gexfix External Fixation |
|----------------------------------|---------------------------------------------------------------------------|-------------------------------------------------------------------|
| Mode of Operation | Fixation with bone locking pins and room temperature implant shape change | Fixation with bone locking pins and room temperature shape change |
| Insertion | Wire/pin driver | Wire/pin driver |
| Pin, wire or implant Biomaterial | 316 Stainless Steel | 316 Stainless Steel |
| Fixator Biomaterial | 17-7 Stainless Steel | Stainless Steel screws & aluminum rail |
| Implant Shape | Round wire/pin | Round wire/pin |
| Fixator Instruments | Stainless Steel Needle Divers | Stainless Steel integral knob |
| Principal of Operation | Shape changing spring acts on pins and wires. | Shape changing power screw and clamps act on pins and wires. |
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| Biomechanics | Moments and forces<br>created on wires and<br>pins apply dynamic<br>forces to bone.<br>Compression can be<br>achieved. | Forces created<br>through power<br>screw activation act<br>on wires and pins to<br>apply static forces to<br>bone. Compression<br>and distraction can<br>be achieved. |
|---------------|------------------------------------------------------------------------------------------------------------------------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| Packaging | Sterile fixator, bone<br>pins, and cover<br>in Tyvek chevron<br>pouches within a<br>cardboard or plastic<br>container | Metal or plastic<br>sterilization tray |
| Sterilization | Gamma sterilized | Non-sterile;<br>sterilized by end-<br>user |
Performance Data: Bench testing included construct pull out, 4-point bending for bone pin, 4-point bending for fixator construct in a bone analog, static ultimate strength in tension bending, fatigue in tension bending and the LINK™ force applied to bone.
## Substantial Equivalence Conclusion
It is concluded that the LINK™ External Fixator and components are substantially equivalent to the predicate device cleared under K160972 and any minor differences between these devices or their performance do not raise any different questions of safety and effectiveness.
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